Antifuses capable of forming localized conductive links

Abstract

The embodiments herein relate to antifuses capable of forming localized conductive links and methods of forming the same. An antifuse is provided. The antifuse includes a substrate, a dielectric liner, and an electrode. The substrate includes a conductor layer, and a trench is in the conductor layer. The trench includes a first conductor surface and a second conductor surface. The dielectric liner is in the trench. The electrode is on the dielectric liner in the trench, and the electrode includes a first electrode surface and a second electrode surface converging to the first electrode surface.

What is claimed is: 
     
         1 . An antifuse, comprising:
 a substrate;   a conductor layer in the substrate;   a trench in the conductor layer, the trench including a first conductor surface and a second conductor surface;   a dielectric liner in the trench; and   an electrode on the dielectric liner in the trench, the electrode comprises a first electrode surface and a second electrode surface converging to the first electrode surface.   
     
     
         2 . The antifuse of  claim 1 , wherein the first electrode surface and the second electrode surface converge at a first angle of at most 90 degrees. 
     
     
         3 . The antifuse of  claim 2 , wherein the first electrode surface adjoins the second electrode surface at a corner. 
     
     
         4 . The antifuse of  claim 2 , wherein the first conductor surface and the second conductor surface converge at a second angle substantially equal to the first angle. 
     
     
         5 . The antifuse of  claim 1 , wherein the first electrode surface is substantially parallel to the first conductor surface. 
     
     
         6 . The antifuse of  claim 1 , wherein the electrode and the conductor layer comprise an electrically conductive material, and the electrically conductive material of the electrode is different from the electrically conductive material of the conductor layer. 
     
     
         7 . The antifuse of  claim 1 , wherein the electrode at least fully occupies the trench. 
     
     
         8 . The antifuse of  claim 1 , wherein the substrate further comprises:
 a base substrate layer;   a buried insulator layer over the base substrate layer; and   a semiconductor layer over the buried insulator layer, wherein the conductor layer is a doped portion of the semiconductor layer.   
     
     
         9 . The antifuse of  claim 8 , wherein a portion of the conductor layer is vertically between the trench and the buried insulator layer. 
     
     
         10 . The antifuse of  claim 8 , wherein the trench extends through the conductor layer, and the first conductor surface is spaced apart from the second conductor surface. 
     
     
         11 . The antifuse of  claim 10 , further comprising an opening in the electrode, wherein a portion of the dielectric liner is exposed in the opening. 
     
     
         12 . The antifuse of  claim 11 , wherein the portion of the dielectric liner is directly in contact with the buried insulator layer. 
     
     
         13 . The antifuse of  claim 8 , further comprising an undoped semiconductor layer in the semiconductor layer, and the conductor layer is between the undoped semiconductor layer and the buried insulator layer. 
     
     
         14 . An antifuse, comprising:
 a substrate having an upper substrate surface;   a conductor layer in the substrate;   a trench in the conductor layer, the trench including a first conductor surface and a second conductor surface;   a dielectric liner in the trench;   an electrode on the dielectric liner in the trench, the electrode comprises a first electrode surface and a second electrode surface converging to the first electrode surface; and   a conductive link between the conductor layer and the electrode, the conductive link extending through the dielectric liner.   
     
     
         15 . The antifuse of  claim 14 , wherein the first electrode surface and the second electrode surface converge to a corner, and the conductive link extends from the corner. 
     
     
         16 . The antifuse of  claim 14 , wherein the electrode comprises an electrically conductive material and the conductive link includes at least the electrically conductive material of the electrode. 
     
     
         17 . The antifuse of  claim 14 , wherein the first conductor surface and the second conductor surface adjoin the first conductor surface at a first corner, the first electrode surface adjoins the second electrode surface at a second corner, and the second corner is vertically over the first corner. 
     
     
         18 . The antifuse of  claim 14 , further comprising an opening in the electrode to divide the electrode into a first electrode section and a second electrode section, and a portion of the dielectric liner is exposed in the opening. 
     
     
         19 . The antifuse of  claim 18 , wherein each electrode section includes the first electrode surface on the dielectric liner and an end surface in the trench, wherein the end surfaces of the electrode sections are substantially vertically straight. 
     
     
         20 . A method of forming an antifuse, comprising:
 forming a conductor layer in a substrate;   forming a trench in the conductor layer;   forming a dielectric liner conformal lining the trench; and   forming an electrode on the dielectric liner, the electrode comprises a first electrode surface and a second electrode surface converging to the first electrode surface.